Many people who drive a small vehicle on vacation have found that the trunks of those vehicles will not accommodate more than one suitcase. Therefore, I pack my clothes in garbage bags rather than my suitcase.
It’s easy to arrange this soft package around some of the other, more rigid contents of my trunk. In addition to avoiding putting my clothes in suitcases, I also don’t pack my shoes in my suitcase but leave them free to be put between my other items.